Printing machines



Feb. 6, 1962 F. K. LAKE PRINTING MACHINES 5 Sheets-Sheet 1 Filed Sept. 14, 1959 INVENTOR. FRANCIS K. LAKE 9. O in f m ATTORNEYS Feb. 6, 1962 F. K. LAKE PRINTING MACHINES Filed Sept. 14, 1959 5 Sheets-Sheet 2 N QE INVENTOR.

FRANCIS K. LAKE- ATTORNEYS Feb. 6, 1962 F. K. LAKE 3,01

PRINTING MACHINES Filed Sept. 14. 1959 5 Sheets-Sheet 3 FIG. 4

INVENTOR. FRANCIS K. LAKE g WWW/ M ATTORNEYS Feb. 6, 1962 F. K. LAKE 3,019,727 PRINTING MACHINES Filed Sept. 14, 1959 5 Sheets-Sheet 4 INVENTOR. FRANCIS K. LAKE BY Maw/m ATTOR N'EYS Feb. 6, 1962 F. K. LAKE PRINTING MACHINES 5 Sheets-Sheet 5 Filed Sept. 14, 1959 INVENTOR. FRANCIS K. LAKE ATTORNEYS United rates Patent Gfifice asters? Patented Feb. 6, 1962 3,619,727 ERWTHNG MACHINES Francis K. Lake, Euclid, tihio, assignor to Addressegraph-Multigraph Corporation, Cleveland, Ohio, a corporation of Delaware Filed Sept. 14, 1959, Ser. No. 839,762 16 Claims. 81. 101-448) This invention relates to printing machines and in particular to lithographic off-set machines. More specifically, the present invention relates to means for furnishing the ir1k-repellent material to the lithographic master.

The principle employed in printing machines of the aforesaid character is that of the immiscibility or incompatibility of oil and water. Thus, a master sheet is prepared bearing the image to be duplicated, and this image is delineated with material receptive to a greasy lithographic ink. The nature of the master is such that background areas of the master surrounding the images are hydrophilic and accept water only. In the operation of such a machine, the master is mounted on the surface of a rotatable master cylinder and both greasy ink and an ink-repellent solution, essentially aqueous in nature, are transferred from respective reservoirs or fountains, by means of roller trains, to the imaged surface of the master, whereby the aqueous repellent solution coats only the unimaged portions of the master rendering these repellent to ink, and the greasy, imaged portion of the master picks up the ink only and rejects the water. The ink on the original master image is thereafter transferred to a so-called blanket on a blanket cylinder, and the image on the blanket is in turn off-set to the paper or other material to be printed.

These ink and repellent roller trains may apply the respective solutions independently to the master, or the arrangement may be such that both the ink and repellent materials are fed to a common form roller which is engageable with the master. In either case, the balance between the ink and ink-repellent solutions is to be maintained within close tolerances. Also, in some duplicating machines as heretofore known, machine levelness is a factor affecting the application of the ink-repellent so that the most satisfactory performance should take into account machine levelness to eliminate gravity flow and assure uniform distribution of repellent solution.

Accordingly, it is a primary object of this invention to enable the ink and ink-repellent solutions to be easily and accurately balanced in a lithographic printing machine, and a related object is to render the ink repellent solution applicator in a lithographic printing machine less dependent on accurate machine levelness for satisfactory operation in comparison to units heretofore known.

The problem of obtaining and maintaining an accurate balance between the ink and ink-repellent solutions is especially acute in those printing applications where resort is had to magnetic ink, as for example, in the printing of bank checks with magnetizable images capable of magnetic sensing in automatic check sorting machines. In fact, in such applications involving magnetic ink, even the height of the individual characters in the printed image is sometimes critical so that there is a definite need for precision regulation of the ink and ink-repellent solutions which are applied to the master plate in the entailed lithographic printing operation. It is therefore another object of this invention to incorporate in a lithographic printing machine an ink-repellent solution applicator which enables the flow of the repellent solution to be manually varied in a precise manner, and an object related to this is to provide an ink-repellent solution applicator in which the quantity of repellent solution is highly responsive to such a manual adjustment.

In ink and moisture applying apparatus previously incorporated in lithographic printing machines, and especially in those arrangements wherein the ink and watercontaining solutions are applied to a common form roller as mentioned above, there has sometimes been a tendency for the ink to backup along the ink-repellent solution roller train and become mixed with the ink-repellent solution in the ink-repellent fountain or reservoir, and another object of the present invention is to overcome this, and specifically to accomplish this by incorporating in an inkrepellent roller train rollers having granulated porous Surfaces, and in particular in combination with one roller having an oleophobic rubber surface.

in order that the above noted lithographic masters may be removed from or replaced on the master cylinder, it is often necessary to manually rotate the master cylinder in a direction reverse that which occurs during the normal printing operation. The repellent solution roller trains as heretofore constructed generally have been geared for rotation with the master cylinder, and these conventional repellent solution roller trains sometimes forward an excessive quantity of repellent solution to the master cylinder upon such reverse rotation, thereby upsetting the balance between the ink and ink-repellent solutions at the master, and it is another object of this invention to overcome this by associating rollers with the fountain roller in the moistening train under circumstances where only a well regulated quantity of ink-repellent solution is presented to the master regardless of the direction of rotation of the master cylinder and roller train.

It is another object of this invention to incorporate in an ink-repellent solution roller train at least one roller having a grained or granulated surface obtained from graining the surface with an aluminum oxide grit blast so as to render such surface porous to have the capacity to store and retain a predetermined large quantity of inkrepellent solution thereon well in excess of that required for the normal passage of repellent to the imaged master,

Advantageously, a roller having the porous absorbent surface can be the fountain roller, and another object of the present invention is to associate therewith a metering roller in the fountain and which is adjustably engageable with the porous surface of the fountain roller to regulate the quantity of repellent solution retained on the granulated surface thereof. Resultantly, the basic flow rate of a repellent solution through a roller train which incorporates such rollers may be regulated by the adjustable engagement of the metering roller with the porous or granulated surfaced fountain roller. A further object of the present invention in this same connection is to utilize a distributor. roller having a like porous surface, and hence capacity to retain excess repellent, thereby interposing an early Oleophobic block to ink back-up.

In printing machines of the kind under construction, it is common to employ a ductor roller for transferring repellent solution from the fountain roller to the distributing roller, and another object of the present invention is to mount the ductor roller in a carriage which is pivotal about an axis of the fountain roller such that rocking movement of the carriage intermittently engages and disengages the ductor roller with the distributor roller to egulate the amount of repellent solution applied to the distributor roller. This carriage comprises two members which are adjustably positionable with respect to one another in a manner such that one of said members is movable toward and away from a cam in the machine which is rotatable with a master cylinder, whereby adjustment of the carriage to move said one member toward the cam reduces the amount of repellent solution transferred to the distributor roller and the master by increasing the portion of the rotational cycle of the master cylinder that is effective to rock the carriage and disengage the ductor roller from the distributor roller.

Yet another object of this invention is to incorporate in a repellent solution roller train individual rollers mounted in a manner such that the individual rollers are movable to a latched position wherein the rollers are spaced one from the other during inoperative periods of the lithographic printing machine.

It is yet another object of this invention to provide an ink-repellent solution applicator for use with a litho" graphic printing machine which enables the foregoing objects to be accomplished and which can nevertheless be installed in a Wide range of conventional lithographic printing machines to replace existing repellent solution applicators with a minimum of modifications to the existing printing machine structure.

Qther and further objects of the present invention will be apparent from the following descriptions and claims and are illustrated in the accompanying drawings, which, by way of illustration, show a preferred embodiment of the present invention and the principles thereof and what is now considered to be the best mode contemplated for applying these principles. Other embodiments of the invention embodying the same or equivalent principles may be used and structural changes may be made as desired by those skilled in the art without departing from the present invention and the purview of the appended claims.

In the drawings:

FIG. 1 is a perspective View, with the side covers removed, of a portion of a lithographic printing machine and illustrates an ink-repellent solution applicator constructed in accordance with this invention;

FIG. 2 is an end elevation view of the portion of the lithographic printing machine illustrated in FIG. 1, illus- 'trating in bold outline the disposition of the elements of the repellent solution applicator roller train in an operative position, and illustrating in phantom outline the disposition of various parts of the repellent solution applicator in a night latch, or inoperative position;

FIG. 3 is an exploded view showing details of the assembly of the component parts of an adjustable, tiltable carriage which is incorporated in the repellent solution applicator illustrated in FIGS. 1 and 2',

FIG. 4 is an enlarged detail view of a camming element incorporated in the carriage which is illustrated in FIG. 3, and shows the reverse side of the camrning element from that visible in FIG. 3;

FIG. 5 is an end elevation view of the carriage shown in the exploded view of FIG. 3;

FIG. 6 is a schematic end elevation view of the carriage shown in FIGS. 3 and 5 and illustrates in bold outline the position of the carriage, and the transfer roller mounted within the carriage, with respect to a distributor roller for one extreme position of an actuating cam and illustrates in phantom outline the position of the carriage and transfer roller with respect to the distributor roller for the other extreme position of the cam.

In FIGS. 1 and 2, there is illustrated an upper head portion 11 of a lithographic printing machine which incorporates an ink-repellent solution applicator constructed in accordance with this invention. This portion of the machine comprises a pair of side frame members 1213. and 12L. A master cylinder 13 is rotatably mounted between the side frames IZR and 12L, and each of the side frame members 12R and 12L is pivotal about a lower pivot point, which is not illustrated in FIG. 1, so that the entire upper head portion 11 may be moved toward and away from a blanket cylinder 14 which is mounted between side frame members ISR and 15L of a lower head portion of the lithographic printing machine.

A hand lever 16 and an adjustable ink 1.7 afford means for adjusting the spacing between the master cylinder 13 and the blanket cylinder 14 by pivoting the side frame members 12 (MR and 12L, that is) toward or away from the side frame members 15R and ESL. Thus, the master cylinder 13 may be positioned by the operator to transfer an image to the blanket on the blanket cylinder 14, or the master cylinder may be spaced from the blanket cylinder so that no image may be transferred therebetween. In either event the master cylinder is rotated with the blanket cylinder through intermeshing gears MG and 3136.

The upper head includes an ink roller train (not shown) for transferring ink from an ink fountain (not shown) to the master cylinder and incorporates a series of rollers which are rotatably mounted between the side frame members 12R and 12L of the upper head portion 11 of the printing 1 iachine. The ink roller train terminates in a pair of form rollers of which one form roller 18 is visible in FIG. 2. The form rollers are directly engageable with the imaged surface of a master mounted on the master cylinder 13 to thereby transfer the ink from the form rollers to the imaged areas of the master. As will be described hereinafter, the form rollers are also operative to transfer the aqueous base ink repellent solution to the non-imaged portions of the master. Each of the form rollers is provided with hand levers 3.9 which may be manually rotated to position eccentric mounts to space the form rollers 18 from the surface of the m "ter cylinder 13 during inoperative periods of the Pfir ng machine. An intermediate roller 21, shown. in dashe outline in FIG. 2, engages both of the form rollers to sup ply ink thereto.

As viewed in FIG. 1, a hand wheel 22 is provided for manually rotating an ink-fountain roll in a fountain of ink, which is not visible in HS. 1. In normal operation, the ink fountain roll is driven by means of a disc 23 on which one endof a crank arm 24 is eccentrically connected. At its opposite end the crank arm is provided with a pawl element, not visible in FIG. 1, which engages gear teeth 25 provided at one end of the ink fountain roller shaft. A hand lever 2 shown in FIG. 1, may be positioned to move a shroud over the gear teeth 25 to vary the portion of the stroke of the crank 24- that is effective to rotate the ink-fountain roller. Also as viewed in FIG. 1, the upper edges of the side frames 12 are slotted at 27 and 28 to afford guides for mounting ink rollers 2% and 31 therein.

In accordance with this invention, an ink-repellent applicator, designated generally by the reference numeral 41 in FIG. 1, is mountable as a unit on the side frame members 12R and 12L of the upper head portion 11 of the printing machine. As viewed in FIG. 1, the applicator 41 is provided with a pair of brackets 42R and 42L which are attachable by means of cap screws as 43 to the upper edges of the side frame members 12R and 12L. A trough member 44 extends between and is attached to the brackets 42 in a manner such that the bracket members and the trough member constitute a frame for the applicator 41. The upper, inner surface of the trough 44 is generally concavely curved so as to afford a fountain for containing a supply of ink-repellent solution. The trough 44 has a bottle receptacle 45 formed integral with a rearward edge of the trough as viewed in FIG. 1. A bottle 46, as viewed in FIG. 2, may be positioned within the receptacle 45 to supply ink-repellent solution to the trough. The level of the ink-repellent solution within the trough may be maintained at a substantially constant level by automatic valve means as known in the art. As viewed in FIG. 1, a flexible hose 47 is provided for draining the ink-repellent solution from the trough 44 during inoperative periods of the machine. During operation of the printing machine, the drain hose 47 may be retained in the position illustrated in FIG. 1 by spring clips 48 and 4% which are attached to the rearward edge of the trough 44.

The ink-repellent applicator 41 comprises a train of rollers for transmitting the ink-repellent solution to the form roller 18 heretofore described. The roller train includes a fountain roller 51, FIG. 1, rotatably mounted in the trough 44 so as to have a portion of the roller immersed in the solution contained within the trough.

As viewed in FIG. 2, the train of repellent applying rollers also includes a distributor roller 52, FIG. 2, which is engageable with the form roller 18 to transfer the ink-repellent to the form roller. A pair of arm members 53R and 53L, FIG. 1, are pivotal about stub shafts 54R and 54L at the rearward ends of the arm members 53 as viewed in FIG. 1, and these arms serve to support the distributor roller 52 as in apertures 55 formed in the forward portions of the arm members 53. Thus, the arm members 53 afford a carriage in which the ductor roller is rotatably supported. The stub shafts 54R and 54L are attached at their innermost ends to the bracket members 42. Thus, the distributor roller 52 is swingable in an are about the axis of the stub shafts 54 so as to be movable into and out of engagement with the form roller 18 for a purpose to be described hereinafter.

The repellent applying roller train also includes a duetor roller 56, FIG. 2, which is disposed intermediate the fountain and distributor rollers and is engageable with the surface of each roller. The ductor roller 56 has shaft ends 57R and 571. which are received in ball bearing mounts of which one mount 58L is visible in FIG. 1. The ball bearing mounts are in turn received within a slotted guide in a ductor carriage designated generally by the reference numeral 59 in M65. 1 and 2, and which is mounted for pivotal action about the axis of the fountain roller in a manner to be described in greater detail hereinafter with reference to FIG. 3. It should be noted at this point, however, that the carriage 59 permits the ductor roller 56 to be moved into and out of engagement with the distributor roller 52 in a duotoring action. The ductor roller is in constant contact with the fountain roller during normal operation of the machine as will be explained. A pair of adjustable extension knobs 61R and dill, FIG. 1, are threadedly received within flanges 62 at the upper and forward ends of the ductor carriage 59 as viewed in FIG. 1. The extension knobs 61 are effective to vary the biasing force exerted by coil springs as on the ball bearing mounts 58, whereby the pressure between the ductor and the fountain rollers may be adjusted. This relationship of the ductor carriage extension knobs 61 ductor roller, ball bearing mounts 58, and biasing springs 63 is clearly illustrated in FIG. 5.

Referring again to FiGS. 1 and 2, the moisture applicator 41 is also provided with earns 64 and 66 which are engaged with the ball bearing mounts 58 and are fixedly positioned on the repellent applicator 41 as by means of screws 67. The upper surfaces of the earns 64 and 66 are curved upwardly so that upon a sufficient amount of rotation of the carriage 59 in a clockwise direction by grasping the parts 61R and 61L, and lifting these as viewed in FIGS. 1 and 2, the ductor or shiftable transfer roller is spaced from the fountain roller. The cam 64 has an upwardly projecting end portion 64F which acts as a stop to limit such rotation of the carriage 59 in a clockwise direction, as viewed in FIG. 2.

The ductor carriage 59 may be rotated to this limited position, as determined by the portion 64? of the cam 64, to space the ductor roller from the fountain roller during periods when the printing machine is inoperative. This position will be hereinafter referred to as the nightlatch position and is illustrated in phantom outline in FIG. 2. Such spacing of the ductor roller 56 from the fountain roller is desirable in order that the biasing forces exerted by the springs 63 do not produce a deformation of the surface of the ductor roller in particular during extended periods of inoperation wherein the rollers remain in a fixed position with respect to one another.

It is also desirable that the distributor roller be capable of being spaced from the upper form roller 18. A pair of link members 63R and 68L, FIG. 1, inter-connect the ductor carriage 59 and the pivotal arm members 53 for accomplishing this result. As viewed in FIG. 2, each of the links is pivotally connected at a point intermediate the ends thereof to the inner surfaces of the arm members 53 at a pivot 62. The links 68 are formed generally in the shape of an L, and the lower edges of the legs thereof abut fixed stops as 71 on the inner faces of the arms 53 as viewed in FIG. 2. A spring 72 is connected at opposite ends to the inner surface of the arm member 52 and a portion of the lower leg of the related link 68 which is intermediate the stop 71 and the point of pivot 69. Slotted guides '73 are afforded in the upper end portions of each of the links 68. Pin members 74 are formed at each end of the ductor carriage 59 and project outwardly therefrom and through the slotted guide 73 formed in each of the links 68. The slotted guide and pin construction affords a lost motion connection between the ductor carriage 59 and the arm members 53, whereby the ductor roller may be moved out of its wedge position between the fountain and the distributor rollers prior to any swinging movement of the arm members 53 and the distributor roller 52. The spring 72 maintains the toe 6ST, FIG. 2, of the link 68 against the stop 71 so that sides of the guide slots 73 are spaced from the ductor carriage pin 74 in the operative position of the ink-repellent applicator assembly as viewed in the bold outline of FIG. 2. Thus during movement of the ductor carriage 59 to the night latch position shown in the phantom outline in FIG. 2, the pins as 74 engage the ends 73E, FIG. 2, of the links 68 and the arm members 53 are eventually swung about the stub shafts 54 through the action of the connecting links 68 to the position indicated by the phantom outline in FIG. 2, and in this night-latch position each of the rollers 51, 52, and 56 is spaced one from the other.

It is desirable that the entire ink-repellent roller train be movable as a unit to a position wherein the distributor roller is spaced from the upper form roller 18 while the respective rollers of the ink-repellent roller train are nevertheless operatively associated with one another so that the roller train can be driven to uniformly coat the surfaces of the respective rollers with the ink-repellent solution while preventing any transfer of ink-repellent to the lithographic master. For example, after an extended period of inoperation, it is desirable to be able to run the ink-repellent roller train sufficiently long to develop a uniform coating of repellent on the surfaces of the rollers, and in particular to saturate the fountain and distributor rollers, before engaging the distributor roller with the form roller. Such a uniform coating avoids an uneven application of ink-repellent to the master due to insufficiently wetted areas on the ink-repellent rollers.

Spacing means indicated generally by the reference character 76 in FIG. 2 are provided for accomplishing this result. The spacing means comprise a cam member '77 which is mounted on the frame of the upper head portion 11 for pivoting action about a pivot point 78. The cam member 77 includes a stud 79 threadedly received Within a recessed edge formed in the upper portion of the cam member. The stud 79 is adjustably positionable with respect to the cam member 77 and may be maintained at any desired adjusted position by tightening a lock nut 81.

As illustrated in FIG. 2, the upper head portion of the stud 79 abuts an outer surface of a brass bearing mount 82 of the distributor roller 52. Because the distributor roller 52 is mounted in a fixed position with respect to the arm member 53, adjustment of the stud 79 is effective to vary the pressure engagement between the distributor roller 52 and the upper form roller 18. A hand lever 83 is attached to the cam member 77 and is effective to rotate the cam member 77 in a clockwise direc tion, as viewed in FIG. 2, to engage the uppermost curved surface 773 of the cam member with the ball bearing mount 82 and displace the arm member 53 upwardly a slight amount to separate the distributor roller 52 and the upper form roller 13. In this position of the dis tributor roller, the ink-repellent roller train may be driven to uniformly coat the exterior surfaces of the inkrepellent rollers with the repellent solution prior to transmitting such repellent solution to the upper form roller and lithographic master.

It is often desirable to give the lithographic master a preliminary treatment by wiping the master with a suitable solution before beginning the normal printing operations. A material applicator for applying such a solution is described in detail in the lanlce et al. Patent No. 2,798,426, and mechanism similar to that described in that patent can be readily mounted on the ink-repellent applicator 41 constructed in accordance with this invention. Thus, referring to FIG. 1, it is seen that the mount ing bracket 42L includes a mounting boss as while the frame member 42R includes a concavely curved recess 87 for mounting such a material applicator thereon.

As mentioned hereinabove, the fountain roller 51 is rotatably mounted within the ink-repellent fountain so as to be partially immersed within the ink-repellent solution contained therein. The fountain roller is positively driven through an intermediate drive gear 91, see FIG. 1, which is engaged with gear teeth 136 of the master cylinder. The drive gear 91 is mounted on a shaft 92, FIG. 1, which in turn is rotatably mounted within the stub shafts 541 and 54L.

The distributor roller is also positively driven from the drive shaft 92, by means of a gear train positioned on the exterior surface of the arm member SSL and not visible in the drawings. The distributor roller may be oscillated in an axial direction if desired.

In accordance with this invention, the outer surface of the fountain roller 51 is preferably metallic and is granulated or pocked so as to have the capacity to store a quantity of ink-repellent solution thereon. The pores afforded by the granulated surface become completely filled with the ink-repellent solution whereby the fountain roller surface acts as a reservoir and is capable of transferring that portion of the ink repellent solution retained thereon which, in effect, represents an excess over that required to saturate the pores.

A rubber surfaced metering roller 92 is adjustably engageable with the granulated surface of the fountain roller to regulate the quantity of the ink-repellent solu tion that is retained on the surface of the fountain roller presented to the ductor roller 56. The metering roller is disposed wholly above the level of the liquid in the inkrepellent fountain and is retained in position by spring latches. The adjustablity of this metering roller determines the degree of pressure contact exerted by it on the fountain roller and hence provides a regulation of the basic rate of flow of the ink-repellent solution through the repellent roller train. A spring biased lever arrange ment affords the pressure engagement of the metering roller on the fountain roller.

As viewed in FIG. 1, the spring biased lever arrangement comprises a pair of plates 93R and QSL which are fixedly attached to the side walls of the ink-repellent trough 44 by cap screws 94. Each of the plates 93 is provided with an outwardly projecting pin, 95 and 6 respectively. A pair of offset levers 97R and 97L are pivotally connected at their lower ends to the plate 93R and 93L respectively. The offset portions of the levers 97 are provided with a series of apertures 98 and a variable amount of spring tension may be exerted between the plates 93 and the levers 97 by connecting a coil spring 99 between selected ones of the apertures 98 and pins 5 and $6. The force exerted by the spring 9h is transmitted to a pin fill which is engaged with a rearward edge of the lever 97 and which projects from an additional lever 192. Each of the levers M52 is pivotally connected to the inner surface of the plate 93 and is operative to exert a force on the metering roller 92 to produce the above mentioned pressure contact of the metering roller with the fountain roller.

In accordance with this invention the outer surface of the distributor roller is also preferably of a metallic material finely granulated so as to have the capacity to store a quantity of ink-repellent solution thereon. A variety of materials, however, may be employed for the fountain and the distributor rollers. Thus, the distributor and fountain rollers may have surfaces formed of granulated plastic, ceramic, glass, metal, or a paper-base rigid Formica. The important feature is that the surface be granulated so as to have the capacity to store a large amount of the repellent solution thereon. The excess continuouslyavailable quantity of repellent solution that is stored on and somewhat under the surfaces of the distributor and fountain rollers substantially prevents the tendency of ink to back up along the repellent roller train and into the repellent fountain. In this regard metallic rollers, which offer very little aflinity for ink and which relay easily regulable amounts are especially suitable, and by having the ductor roller of an oleophobic rubber this further interposes a block tending to prevent back-up of ink into the repellent fountain. Inasmuch as the ink-repellent solution is metered from the fountain by the above described action of the metering roll and because the granulated surfaces of the fountain and distributor rollers have the capacity to store a large amount of repellent solution, there is substantially no repellent solution carried in the nip between the fountain and ductor rollers. Hence, machine levelness is a less critical factor than with ink-repellent applicators heretofore known.

As described hereinabove the metering roller, which is maintained in preselected pressure engagement with the fountain roller at all times, determines the basic amount of repellent that is transferred through the repellent roller train to the master cylinder. However, additional regulation of the ink-repellent how is afforded by the repellent applicator of this invention. This additional regulation is obtained by a manual adjustment of the relative disposition of component parts of the ductor carriage 59 to modify the ductor action or" the carriage, and it will be recalled that the ductor roller is in continuous contact with the fountain roller.

Referring again to FIG. 1, it is seen that the ductor carriage 5? includes a pair of inwardly projecting cam followers 111R and lllL at both ends of the carriage. A pair of cams 112R and XML are pivotally connected to the repellent applicator frame structure and are biased by springs 113R and REL into engagement with the cam followers 111R and llllL so as to bias the ductor carriage 59 about the axis of the fountain roller, which is the pivotal axis of the carriage, to a position wherein the ductor roller is normally engaged with the distributor roller as shown in FIG. 2. The applicator 4-1 includes a pair of idler gears 114?. and ll iL which are rotatably mounted on the stub shafts 54 and which are driven from gear teeth on the fountain roller shaft. Camming means are mounted on the exterior surfaces of the gears 114 and may comprise circular discs which are eccentrically mounted with respect to the longitudinal axis of the gears 114. One of these discs 115R is visible in FIG. 1. Each end of the carriage 59 includes a cam follower 141, see FIG. 5, which is engageable with the cam as 115R during a portion of the rotational cycle of the cam. Such engagement of the cam and the cam follower pivots the carriage 59 about the axis of the fountain roller to swing the ductor roller out of engagement with the distributor roller and thereby interrupt the transfer of ink-repellent to the distributor roller. Each end of the ductor carriage 59 comprises separate plate members which are pivotally connected together, and the cam follower as 14-1 which is engageable with the rotatable cam as 115R, is carried by one of these plate members which thereby serves as an operating lever for the carriage 59. A manually adjustable knob 116, as viewed in FIG. 1, is operatively connected as will be described to vary relative disposition of the separate plate members of the carriage 59 to move the cam follower 141 toward or away from the cam as 115R and thereby correspondingly vary the portion of the rotational cycle of the cam as 115R that is effective to swing the ductor roller out of engagement with the distributor roller and correspondingly modify the amount of ink-repellent that is transmitted through the roller train to the master cylinder.

The particular construction of the ductor carriage 59 and the manner in which the above noted manual adjustment is obtained will now be described with particular reference to FIG. 3. Both ends of the carriage 59 are alike so that the component parts of only one end have been illustrated in FIG. 3.

In FIG. 3 it is seen that the ductor carriage 59 includes a ductor arm plate 121 and a cam follower plate or operating lever 122. The ductor arm plate is formed with a slotted guide 123 for mounting the ductor roller in one end portion of the plate. A mounting boss 124 projects inwardly from the inner surface of the ductor arm plate and is formed with an inner bore which receives the outer race of a ball bearing 125. An end of the fountain roller shaft 126 has a bore 12% extending axially therethrough and is passed through the inner race of the ball bearing 125 so that the plate 121 is mounted on the fountain roller shaft. A sleeve assembly 127 having exterior gear teeth 127G formed thereon is keyed to the fountain roller shaft 126 for rotation therewith. The gear teeth 1276 are in mesh with the idler gear Ll-1R and afford the drive for this gear and the cam disk as 115R which is eccentrically mounted thereon. Thus the master cylinder drives the fountain r ller through the gear 91, see FIG. 1, and the fountain roller drives the cam disks 115R. A circular boss 12% projects axially outwardly from the outer surface of the ductor arm plate 121 and includes a cylindrical outer surface and an inner bore 13%, both of which are concentric with the axis of the fountain roller shaft 126 as received within the mounting boss 124. A pivot pin 129 projects axially outwardly from the outer surface of the ductor arm plate 121 at an end portion of the plate which is opposite that containing the slotted guide 123. The ductor arm plate 121 also includes a stub shaft 131 and a pin '74 both of which project from the outer face of the plate 121. As described hereinabove, the pin 74 affords a connection between the carriage 59 and the links 68 for swinging the distributor roller into the night-latch position.

The cam follower plate 122 includes a circular aperture 132 for receiving the pivot pin 129 of the ductor arm plate. The cam follower plate includes a generally rectangular-shaped slotted guide 133 in a central portion thereof. A pin 134 projects from an inner face of the cam follower plate 122 and the cam follower 111R is mounted on the pin 134 and is retained thereon by a. snap ring 135. The cam follower plate includes an aperture 136, which extends therethrough, and an internally threaded aperture 137.

An adjustable cam follower assembly, designated generally by the reference numeral 13%, is positionable on the inner face of the cam follower plate 122. The cam follower assembly includes a shaft member 139 which is passed through the aperture 136. A pin 1391 is eccentrically positioned on the shaft member 139. A cam follower 141 is mountable on the pin 1391 by a snap ring 142. The shaft member 139 is also formed with a flange portion having a keyway 139K. An adjustment plate 143 is interposed between the flanged head of the shaft member 139 and the inner face of the cam follower plate 122. The adjustment plate 143 includes an arcuately shaped slot 144 in one end portion and a generally circular aperture 145 in another portion thereof. A key 146 projects inwardly from the periphery of the aperture 145 and is disposable in the lceyway 139K so that adjustment of the adjustment plate 143 produces a corresponding movement of the shaft member 139 and eccentric pin 1391 A nut 147 and a washer 1 58 are threadedly receivable upon the shaft member 139 to retain this mernber within the aperture 136. A washer 151 and a locking screw 149, which is receivable within the internal aperture 144, affords means for retaining the plate 143 and the shaft 1b member 139 at any adjusted position of the eccentric pin 139i and cam follower 141 with respect to the cam follower plate 122.

A generally square-shaped male slide plate 152 is slidably positionable within the rectangular-shaped slot 133 so as to be movable in only one coordinate direction as indicated by the arrows X in FIG. 3. The squareshaped male slide plate is formed with a circular, central aperture 153.

A shaft 154 is rotatably received within the bore 13 of the boss 123 and is also rotatably received within the bore 121) of the hollow fountain roller shaft 126. The shaft 154- projects outwardly of the ductor arm and cam follower plates 121 and 122 at either end of the carriage 5%. Each end of the shaft 154 includes a keyway 154K and a pin-receiving aperture 1541.

A rotatable eccentric cam member 155 includes a circular boss tea which projects from an outer face of the cam member and has a circular bore 157 through which the shaft 154 is passed. As viewed in FIG. 4, the cam member 155 has a circular boss 15? which projects axially inwardly from the inner face of the cam follower. The boss 158 includes an inner, circular bore 159 which is rotatably received on the exterior cylindrical surface of the boss 123 formed on the ductor arm plate 121. The bores 157 and 159 and the exterior surface of the cylindrical boss 156 are concentric about the axis of the shaft 154 and the fountain roller shaft 126. The exterior cylindrical surface of the boss 158, however is eccentric about this axis and is rotatably received within the bore 153 of the male slide plate 152. Apertures 161 are formed in the boss 156 and a tapered locking pin 162 is passed through an aperture 161 and into the aperture 15a? to lock the shaft 154 to the eccentric cam member 155 so that the eccentric cam members at the opposite ends of the carriage 159 may be simultaneously rotated. The eccentric cam member 155 additionally includes a series of threaded apertures 163.

A sector gear 16 includes a central bore 165 through which the boss 156 is passed and additionally includes apertures 166 aligned with the apertures 163 of the eccentric cam member 155. A plurality of screws 167 are passed through the apertures 166 and threadedly received within the apertures 163 to mount the eccentric cam member 155 for rotation with the sector gear 15 The manual adjusting knob 116 heretofore described is formed with a hollow shaft 168 having a pinion gear 169 at the end thereof. The pinion gear 169 engages the teeth of the sector gear 164 and the hollow shaft 163 is rotatably mounted on the stub shaft 131 of the ductor arm plate 121 and retained thereon by a washer 171 and a snap ring 172.

An indicator 173 having a pointer 1731 is interposed on the stub shaft 131 between the end of the shaft 168 and the outer face of the ductor arm plate 121. A screw 174 locks the indicator 173 in a fixed position on the ductor arm plate. The pointer 1731 is movable along the outer face of the sector gear 164 during rotation of the gear to indicate the adjusted position of the ductor arm and cam follower plates 121 and 122 of the carriage 59.

The eccentric disposition of the outer cylindrical surface of the boss 158 with respect to the axis of the fountain roller shaft permits the cam follower plate 122 to be swung about the pivot pin 129 of the ductor arm plate and thereby move the cam follower 14-1 either toward or away from the related cam 115R by manual rotation of the rotatable eccentric cam member 155. The axis of the fountain roller shaft is a fixed and immovable axis for the ductor carriage 59 by reason of the mounting of the fountain roller in the moisture applicator frame structure. Additionally, the ductor carriage 59 is spring biased to a limiting position wherein the ductor roller engages the distributor roller assuming that the cams 115 ii are rotated to the position wherein the peripheries of the cams are spaced from the cam followers 141. This spring biasing force is afforded by the cams 112 which act on the cam followers 11114 and 111R as described with reference to FIG. 1.

Thus, adjustment of the knob 116 rotates the sector gear and the eccentric cam member 155 so that the geometric center of the outer cylidrical surface of the boss moves in a small circular are about the center of rotation of the boss, which is the axis of the fountain roller. This movement of the eccentric boss 15$ acts on the bore 153 of the male slide member 152 to cause a corresponding displacement of the slide member. The slide member 152 is free to move in the coordinate direction XX, as indicated by the arrows in FIG. 3, along a line passing through the centers of pivot pin and the boss 128 within the rectangular slot 133 of the cam follower plate so that no relative motion between the ductor arm plate and the cam follower plate in that co ordinate direction is obtained. However, the slide me .1.- ber is restrained against movement in the coordinate direction YY, as indicated by the arrows in HG. 3, so that rotation of the eccentric boss 15?; is effective to move the cam follower plate 122 in that coordinate direction about the pivot pin 129 of the ductor arm plate, which is maintained in a fixed, stationary position by the spring bias exerted on the cam follower 111R. This rotational movement of the cam follower plate 122 about the pivot pin 129 moves the cam follower 141 either toward or away from the cam 115R.

Assuming that the direction of rotation of the adjusting knob 116 is such that the cam follower 141 is moved toward the cam 115R, a greater portion of the periphery of the cam is effective to pivot the entire ductor carriage 59 about the axis of the fountain roller shaft, and against the spring bias exerted on the cam follower 111R, to move the ductor roller out of fluid transmitting engagement with the distributor roller. Thus, a greater portion of the rotational cycle of the cam is effective to interrupt contact between the ductor and the distributor rollers and thereby reduce the amount of inkrepellent transmitted through the roller train.

Rotation of the adjusting knob 116 to move the cam follower 141 away from the cam 115 permits the ductor roller to be engaged with the distributor roller for a longer portion of the rotational cycle of the cam 115 and therefore increases the amount of repellent trans mitter to the master cylinder through the roller train.

The eccentric adjustment afforded by the above described mechanism permits a quite precise and continuously variable regulation of the flow of the ink-repellent solution inasmuch as the basic range of repellent fluid flow is obtained through the action of the metering roller.

FIG. 6 graphically illustrates the ductor action ob tained with the ductor carriage 59 in any one given position of adjustment of the component parts of the carriage. With the cam 115R rotated to the position shown in the bold outline the spring 113 exerts a bias on the carriage 59 through the cam follower 11.1 to tilt the carriage about the axis of the fountain roller shaft to a position wherein the ductor roller 56 is engaged in repellent transmitting engagement with the distributor roller 52, as shown in the bold outline. Upon rotation of the cam 115R to the position shown in the phantom outline, the carriage 59 is tilted in a clockwise direction, as viewed in FIG. 6, about the axis of the fountain roller shaft to a position wherein the ductor and distributor rollers are spaced one from another and the transfer of repellent therebetween is interrupted.

The operation of the repellent applicator of this invention is largely self-evident from the foregoing description but will now be briefly reviewed. Assuming that the operation is initiated from a night-latched position of the roller train, the metering roller is inserted in snap-in mounts provided in the side walls of the repellent fountain. The ink-repellent solution is added to the fountain and the roller train is moved from the nightlatch position to the operative position as illustrated in FIGS. 1 and 2. The separator lever 83 is moved to an upward position, clock-wise as viewed in P16. 2, to space the distributor roller from the upper form roller. The power is turned on and the roller train is driven until all of the rollers are thoroughly and uniformly coated with the repellent solution. The separator lever 83 is then turned to the down position to engage the distributor roller and the upper form roller and the duplicating process can then be initiated. Advantageously, this is so with the pointer 1731 of the manual adjustment mechanism aligned with a central adjustment mark on the sector gear 164, and more-or-less ink-repellent may be applied thereafter by suitable adjustment of the knob 116.

The fountain and distributor rollers are preferably of steel grit blasted with No. 54 aluminum oxide grit. This grit has an average diameter of 0.012 and conditions are such as to produce pores in the steel surface of the roller having a depth of 125 to 140 (root means square) micro inches measured by a brush analyzer. The peaks between pores or valleys are rather sharp and in order to reduce the possibility of wear-down ultimately resul ing in poor repellent absorbing or holding power, the surface of the roller is plated with chromium to a depth of about 0.0015" to 0.002". Most of the plating is on the tops of the peaks, but there is some thin plating of the bottoms and sides of the pore pockets such that in the final analysis the pores are to micro inches deep. This is more chance than purpose since the bottoms of the pores essentially need not be chrome plated, and I therefore prefer a pore depth not much in excess of micro inches and an average pore diameter approximately that of the No. 54 grit, namely, about 0.012 to hold water without draining. The minimum diameter of a pore is simply that sufficient to absorb and pass water (repellent) by capillarity. However, grit as small as No. 1000 can be effectively used (average diameter 0.00028).

Thus, in accordance with this invention a novel inkpropellent applicator for use with lithographic printing machines is afforded. The applicator incorporates fountain and distributor rollers which have porous surfaces so as to have the capacity to store a quantity of the ink-repellent solution thereon. Preferably these rollers are of a suitable rigid material such as metal and the metering and ductor rollers are rubber surfaced since this relationship, particularly the rigid surfaces, enables exceedingly fine control to be exerted on the amount of repellent passed to the master cylinder. Thus, the fineness of the granulation and porosity of the surface of such rollers plus the essentially unyielding nature of the fountain and distributor rollers in conjunction with the pressure adjustments described governs the amount of inkrepellent that can be transferred through the roller train. The manner in which large amounts of repellent can be stored on the surface of the granulated rollers independent of normal operational requirements inhibits a feed back of ink from the form roller and through the repellent roller train to the repellent fountain. An oleophobic rubber roller may be incorporated as an intermediate roller between two granulated surfaced rollers to further inhibit such ink feed back.

The ink-repellent applicator also incorporates a granulated surface fountain roller and a metering roller which is adjustably engageable with the fountain roller to provide a basic range of regulation of the quantity of inkrepellen-t that is'transrnitted through the applicator roller train. The metering roller restricts the amount of repellent carried by the fountain roller to a regulated quantity, and the granulated surface of the fountain roller retains this regulated quantity of repellent solution in a distributed state so that accurate machine levelness is less of a critical factor than repellent applicators heretofore known.

Thus, the metering roller and extent ofsurface porosity of the fountain roller determines in the first instance the quantity of repellent solutions capable of transfer to the ductor roller. Adjustment of the latter for the period of its engagement with the distributor roller and the degree of porosity of the distributor roller determines the extent to which the latter will pick up repellent from the ductor roller. Control over the amount of moisture relayed to the master plate is not dependent solely in the degree of pressure contact between the ductor and fountain roller, and restriction of moisture flow under the present invention is compensated for by establishing a long dwell between the ductor and the distributing roller.

The ductor carriage incorporates separate plate members which are adjustably positionable one with another so that a cam which is rotatable with the master cylinder has a variable effect in producing swinging movement of the ductor carriage.

The ductor roller and the metering roller are effective to regulate the quantity of repellent retained on the fountain roller regardless of the direction of rotation of the fountain roller so that an over-supply of repellent solution to the master cylinder, as upon a manual reverse rotation of the master cylinder, is avoided.

The repellent applicator of this invention incorporates latching mechanism for moving the rollers of the roller train to a position wherein the rollers are spaced one from the other during inoperative periods of the machine.

A separator lever is provided for spacing the applicator repellent roller train from the form roller of the main printing machine so that the repellent roller train may be power driven to thoroughly coat the individual rollers of the train with repellent solution prior to initiation of the duplicating or printing machine.

Additionally the applicator is mountable as a unit on existing lithographic printing machines. Hence, while I have illustrated and described the preferred embodiments of my invention, it is to be understood that these are capable of variation and modification, and I therefore do not wish to be limited to the precise details set forth, but desire to avail myself of such changes and alterations as fall within the purview of the following claims.

I claim:

1. A repellent system for applying ink repellent to the form roller of a lithographic printing machine which includes a master cylinder and comprising, a fountain for holding a supply of repellent, a fountain roller rotatable in the fountain, a distributor roller engageable with the form roller, a cam rotatable with the master cylinder, a ductor roller shiftable between the fountain and distributor rollers and engageable therewith, and operating means for so shifting the ductor roller including a first member pivotal about the axis of the fountain roller and mounting the ductor roller thereon to continuously engage the fountain roller, means normally urging said first member to engage the ductor roller with the distributor roller, a second member having a direct connection to the first member and having a portion coaxial with the axis of the fountain roller and being adjustably positionable with respect to the first member, said second member being adjustably positionable as aforesaid by way of an eccentric means rotatable about the axis of the fountain roller and effective on a slide mounted within a slot formed in said second member, said second member having a cam follower mounted thereon to be intermittently engaged by said cam for instituting swinging movement of the ductor roller away from contact with the distributor roller, whereby adjustment of the position of the second member through rotation of said cam means varies the portion of the rotational cycle of the cam that is effective to interrupt the transfer of repellent from the ductor roller to the distributor roller.

2. A repellent system for applying ink repellent liquid to the form roller of a lithographic printing machine which includes a master cylinder and comprising, a fountain for holding a supply of repellent, a fountain roller rotatable in the fountain, a ductor roller continuously engaged with the fountain roller, a distributor roller engageable with the form roller, a cam rotatable with the master cylinder, operating means for swinging the ductor roller into engagement with the distributor roller to relay thereto repellent transferred from the fountain roller to the ductor roller and including, a first member pivotal about the axis of the fountain roller and mounting the ductor roller therein, spring means nonnally biasing said first member toward the distributor roller to yieldably engage the ductor roller therewith, a second member selectively positionable about the axis of the fountain roller and being pivotally connected to the first member, the pivotal connection between said members enabling the second member upon a force applied thereto to pivot the first member about the axis of the fountain roller, and means coaxial with the fountain roller for maintaining the second member in a selected position with respect to the first member, the last named means including an eccentric rotatable about the axis of the fountain roller and disposed within said second member and manually adjustable to vary the relative positions of the first and second members, said second member having a cam follower mounted thereon to be intermittently engaged by said carn thereby establishing such a force and producing swinging movement of the ductor roller away from contact with said distributor roller, whereby the adjustment of the lastnamed means varies the portion of the rotational cycle of the cam that is effective to swing the ductor roller out of engagement with the distributor roller.

3. A repellent system roller train for applying ink repellent liquid to a lithographic master on a master cylinder in the machine and comprising, a fountain for holding a supply of repellent, a fountain roller rotatable in the fountain, a ductor roller engaged with the fountain roller, a distributor roller enagageable by the ductor roller, a cam cyclically rotatable with said master cylinder, operating means for swinging the ductor roller about the axis of the fountain roller and into and out of engage ment with the distributor roller to relay and interrupt the relay of repellent between the fountain roller and the distributor roller and including a first member rotatable about the axis of the fountain roller and serving as a support for the ductor roller, a second member directly connected to the first member and adjustably positionable about the axis of the fountain roller and with respect to the first member, said second member having an adjustable cam follower mounted thereon to be intermittently contacted by said cam and producing said swinging movement of the ductor roller, and means for selectively adjusting the second member relative to the first to thereby move said follower relative to said cam and including an eccentric means rotatable about the axis of the fountain roller and disposed within the plane of said second member.

4. In a lithographic duplicating machine of the kind having a rotatable master cylinder and a train of rollers for supplying a repellent solution to the master cylinder including a fountain roller, a distributor roller, and a ductor roller adapted to be automatically rocked into and out of engagement with the distributor roller by cam means rotatable with the master cylinder; a ductor roller carriage mechanism comprising, a first member mounted on an end portion of the fountain roller for a limited amount of rotational movement about the axis of the fountain roller and mounting the ductor roller thereon, said first member having a boss concentric about the axis of the fountain roller, a second member pivotally connected to the first member and having a slot therein, and a cam follower intermittently engageable with the camming means, a plate slidably disposed within the slot in the second member for sliding movement in a radial direction with respect to the fountain roller axis and having a circular aperture extending therethrough, a manually rotatable member having a boss disposed within the circular aperture, the exterior circumferential surface of said boss being eccentric about the axis of the fountain roller, said boss having a circular bore concentric about the fountain roller axis and disposed in encircling relation with the boss on said first member, whereby rotation of said rotatable member is efiective to rotate the second member about the pivotal connection to vary the position of said second member with respect to said first member and the position of the cam follower with respect to the cam cans to vary the relative length of the periods of engagement and disengagement between the ductor and distributor roller during a rotational cycle of the master cylinder.

5. A carriage mechanism for use in a printing machine roller train comprising, first and second plate members pivotally connected together, said first member having a first circular cylindrically surfaced boss projecting therefrom, said second member having a slot therein and having inner edges surrounding and spaced from the cylindrical surface of said boss, at third plate member slidably disposed in said slot for sliding movement in one coordinate direction, said third plate member having a central, circular aperture of greater diameter than said boss, a rotatable member having a second circular, cylindrically surfaced boss projecting therefrom and having a circular bore formed in the projecting end of said second boss, said second boss being positioned in engaging relation with the sides of the circular aperture and the circular bore being positioned in engaging relation with the cy indrical surface of the first boss, said bore being concentric about the longitudinal axis of the first boss, whereby rotation of said rotatable member varies the relative angular position of said first and second plate members about the pivotal connection by sliding the third plate member in said one coordinate direction Within said slot 6. Ina lithographic printing machine of the kind having a master cylinder for holding a master and a form roller for applying both an ink and an ink-repellent to the form roller, a roller train for transferring an ink-repellent from a fountain to the form roller comprising a series of rollers terminating in a distributor roller which is engageable with the form roller, arm members mounting the ends of the distributor roller for rotation therein and pivotally related to frame structure of the printing machine, drive means for rotating said distributor roller concurrently with said series of rollers, and means for pivoting the arm members about the pivotal connection to disengage the distributor roller from the form roller, the last named means including a manually operable cam effective when operated to so pivot the arm members, and an adjustable stud element carried by said cam and normally supporting said arm members to enable the pressure between the distributor roller and the form roller to be varied.

7. In a lithographic printing machine of the kind having a master cylinder for holding a master and a form roller for applying both an ink and an ink-repellent to the form roller, a roller train for transferring an ink-repellent from a fountain to the form roller comprising, a fountain roller rotatable in a fountain of ink-repellent, a distributor roller engageable with the form roller, a ductor roller intermediate the fountain and distributor rollers and engageable with said rollers, and means for simultaneously shifting the ductor and distributor rollers to released positions wherein the ductor roller is spaced from both the fountain and distributor rollers and the distributor roller is spaced from the form roller, the last-named means comprising carriage means pivotally mounted in the machine and rotatably supporting the ductor roller and the distributor roller whereby the carriage means for said distributor roller can be pivoted to disengage the distributor and form rollers, said ductor roller being bodily shiftable in its carriage means to be disengaged from the fountain and distributor rollers, and fixed cam means normally spaced from but engageable by end portions of the ductor roller to shift bodily the ductor roller as aforesaid in upon pivoting the ductor roller carriage means to present said end portions of the ductor roller to said fixed cam means.

8. In a lithographic printing machine of the kind having a master cylinder for holding a master and a form roller for applying both an ink and an ink-repellent to the form roller, a roller train for transferring an inkrepellent from a fountain to the form roller comprising a fountain roller rotatable in a fountain of ink-repellent, a distributor roller engageable with the form roller, a ductor roller intermediate the fountain and distributor rollers and engageable with said rollers, and means for s lifting the ductor and distributor rollers to latched positions wherein the ductor roller is spaced from both the fountain and distributor rollers and the distributor roller is spaced from the form roller comprising, a carriage pivotally mounted for pivoting about the axis of the fountain roller and mounting the ductor roller therein, spring means biasing the ductor roller toward the distributor roller, and cam means for moving the ductor roller against the bias of the spring means and out of engagement with the fountain roller upon movement of the carriage toward said latched position, arm members mounting the ends of the distributor roller for rotation therein and pivotally related to frame structure of the printing machine, and a linkage interconnecting the carriage and the arm members and having a lost motion slot therein, whereby movement of the carriage toward the latched position 'disengage's the ductor and distributor rollers and subsequently dise'ngages both the ductor and fountain rollers and the distributor and form rollers.

9. A repellent unit adapted for bodily attachment to spaced frame members adjacent the top of a lithographic printing machine, and wherein a distributor roller of the unit is to engage a related lower roller in the machine, and comprising a pair of mounting brackets adapted to be rigidly secured to said frame members, a fountain and a related rotatable fountain roller arranged horizontally between said brackets, a manually movable ductor carriage pivotally mounted about the axis of the fountain roller and having a ductor roller rotatably supported thereby, said ductor roller being shiftable bodily in said carriage, a pair of arms pivotally connected to said brackets on a horizontal axis and extending in a forward direction away from said fountain, a distributor roller disposed between said arms and rotatably supported thereby and movable with said arms during upward pivoting of the same to thereby -disengage the distributor roller from said related lower roller of the machine, said ductor roller being engageable with the distributor and fountain rollers, and fixed cam means engageable by end portions of the ductor roller to shift bodily the ductor roller in said carriage and move the ductor roller out of contact with the fountain roller when said carriage is pivoted manually about the axis of the fountain roller.

10. A unit according to claim 9 wherein a connection is afforded between the carriage and the arms which support the distributor roller to move said arms with said carriage when the carriage is pivoted manually as aforesaid.

1 1. A unit according to claim 9 wherein said carriage includes slotted plates, said ductor roller being rotatably supported in bearings disposed in the slots of said plates, and said cam means being engageable with said bearings to produce bodily shifting of the ductor roller.

12. A unit according to claim 11 wherein manually adjustable spring means supported by said bearings in said slots.

13. A repellent unit adapted for bodily attachment'to spaced frame members adjacent the top of a lithographic printing machine, and wherein a distributor roller of the unit is to engage a related lower roller in the machine, and comprising a pair of mounting brackets adapted to be rigidly secured to said frame members, a fountain and a related rotatable fountain roller arranged horizontally between said brackets, a manually movable ductor carriage pivotally mounted about the axis of the fountain roller and having a ductor roller rotatably supported thereby, said ductor roller being shiftable bodily in said carriage, a pair of arms pivotally connected to said brackets on a horizontal axis and extending in a forward direction away from said fountain, a distributor roller disposed between said arms and rotatably supported thereby and movable with said arms during upward pivoting of the same to thereby disengage the distributor roller from said related lower roller of the machine, said ductor roller being engageable with the distributor and fountain rollers, fixed cam means engageable by end portions of the ductor roller to shift the ductor roller in said carriage and move the ductor roller out of contact with the fountain roller when said carriage is pivoted manually about the axis of the fountain roller, an operating lever connected to said carriage to enable the carriage to be pivoted repeatedly between the fountain and distributor rollers, said operating lever having a cam follower in a location predetermined by the position of said lever relative to said carriage, eccentric cam means rotatable about the axis of the fountain roller to selectively reposition said lever and relocate said cam follower, and a continuously rotatable cam engageable with said cam follower.

14. A unit according to claim 13 wherein said cam follower is adjustable independent of said lever to which it is attached.

15. A repellent unit adapted for bodily attachment to spaced frame members adjacent the top of a lithographic printing machine, and wherein a distributor roller of the unit is to engage a related lower roller in the machine, and comprising a pair of mounting brackets adapted to be rigidly secured to said frame members, a fountain and a related rotatable fountain roller arranged horizontally between said brackets, a ductor carriage pivotally mounted about the axis of the fountain roller and having a ductor roller rotatably supported thereby, a pair of arms connected to said brackets and extending in a forward direction away from said fountain, a distributor roller disposed between said arms and rotatably supported thereby, said ductor roller being engageable with the distributor and fountain rollers, an operating lever connected to said carriage to enable the carriage to be pivoted repeatedly between the fountain and distributor rollers to thereby repeatedly disengage the ductor roller from one of the rollers with which it is engageable, a cam arranged on a fixed axis for continuous rotation thereabout during operation of the machine, and an adjustable cam follower on said lever arranged for adjustment independent of said lever toward and away from the path of said cam.

16. In a lithographic printing machine, a train of rollers for transmitting ink repellent from a fountain to the master on the master cylinder of the machine and comprising, a fountain roller and a distributor roller spaced one from another, a ductor roller disposed between the fountain and distributor rollers and mounted in a carriage for constant contact with the fountain roller during normal operation of the machine, said carriage being pivotally mounted in the machine about the axis of the fountain roller to swing the ductor roller into and out of contact with the distributor roller While maintaining said constant contact, and operating means for swinging the carriage including an operating lever adjustable about the axis of the fountain roller and having a direct connection to said carriage for so swinging the carriage when a force is applied to said lever, adjustable cam means to vary the position of said lever about said axis relative to said carriage and including a manually adjustable eccentric rotatable about the axis of said fountain roller, said eccentric being rotatable in a circular opening in a slide movable in the plane of said operating lever, a cam continuously rotatable during operation of the machine, and a cam follower adjustably associated with said lever for variant spacing relative to the path of said cam which applies a force as aforesaid to said cam follower.

References Cited in the file of this patent UNITED STATES PATENTS 151,688 Ehrgott June 9, 1874 1,966,311 Pearson et al July 10, 1934 1,988,970 Hotchkiss Jan. 22, 1935 2,000,518 Horton May 7, 1935 2,622,521 Larsen Dec; 23, 1952 FOREIGN PATENTS 216,990 Australia Aug. 12, 1958 488,444 Great Britain July 7, 1938 

